Production of yellow dye images by color development



United States Patent PRODUCIION 0F YELLOW DYE IMAGES BY COLOR DEVELQRIVIENT Walter F. Holfstadt, Vestal, N.Y., assignor to General Aniline & Film Corporation, New York, N.Y., a corporation of Delaware No Drawing. Application April 3, 1958 Serial No. 726,288

This invention relates to the preparation of photographic yellow dye images by photographic color-forming development.

The production of colored photographic images most generally used in photographic elements is that of colorforrriing development first proposed by Rudolf Fischer in 1912 .and described in Fischer, U;S. P. 1,102,028. In this system, ,an exposed photographic silver halide emulsion is developed with .a pr m y .aromatic amino developer, such as a p-dialkylamino aniline in the presence of a color-forming component. The result Qfthis procedure is the formation, in situ, with. the silver image ofan .azo methine or .quinone mine dyestufi image. The silver image is then removed with mild oxidizing agents such as alkali metal terricyanicles, leaving the unafiected dyestutf image in the emulsion.

Although the production of subtractively' colored images by the Fischer process has found'wide acceptance, being relatively simple to carry out, it possesses one serious disadvantage, to wit, the azo methine and quinoneimine dyes produced thereby are quite unstable in the presence of acid vapors particularly of sulfur dioxide.

In an effort to overcome the-drawbacks of the Fischer method, investigators in the art have turned to other dye systems in order to produce photographic dye images of greater stability.

In U.S.P. 2,486,440, issued to Schmidt and Tulagin, colored photographic images are described in which the dyes are of the azine type and are produced by the color development of an exposed silver halide emulsion a 2,4-diamino aniline in the presence of a color former such as an aromatic compound containing at least one hydroxyl group linked to the aromatic structure. The resulting dyestuif images are much more stable, particularly to acid vapors than are the azo methines or quinoneimines.

However, in adapting the azine dye system to a multilayer film comparable in simplicity to the older method, operators experienced difliculties in producing a permanent yellow dye image simultaneously with magenta and cyan dye images upon color development.

Although yellow images could be produced with the usual keto methylene compounds such as acetoacetaniline, and the like, such images tended to be sensitive to lower pH conditions which resulted in undesirable spectral shifts toward longer wave lengths.

I-t has now been discovered that a more permanent yellow dye image can be produced simultaneously with the cyan and magenta azine dye images by color-forming development with a 2,4-diamino aniline in the presence of a 1-aroyl-5-amino-2-naphthol.

That a coupler should produce an azine yellow dye image is indeed most unexpected and striking since, ordinarily, such yellow dye images are produced from a keto methylene coupler. In this connection, it should be noted that the use of regular p-phenylenediamine type developer produced a cyan dye rather than a yellow with the above coupler.

, 2,921,85I Patented Jan. 19, 196i) be represented by the following general formula:

wherein R represents hydrogen, -NO halogen, i.e., chlorine, bromine, etc.; alkoxy, i.e., methoxy, ethoxy, npropoxy, n-butoxy, sec.-butoxy, n-amoxy, sec.-amoxy, nhexoxy, n-heptoxy, -n-.octoxy, n-nonoxy, n-decoxy, nundecoxy, n-dodecoxy, n-tridecoxy, n-tetradecoxy, npentadecoxy, n-hexadecoxy, n-heptadecony, n-octadec0xy,.nnonadecoxy, etc.; alkyl, i.e., methyl, ethyl, -n=pr9Py1,isopropyl, n-butyl, iso-butyl, n-amyl, iso-amyl, sec.-amyl, n-hexyl, iso-hexyl, n-heptyl, sec.-heptyl, n-octyl, iso-octyl, n-nonyl, iso-nonyl, n-decyl, iso-decyl, n-undecyl, ndodccyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, etc., -NHR wherein R represents hydrogen, alkyl as above for R and an aliphatic acyl group, i.e., acetyl, n-propionyl, n-butyryl, valeryl, capronyl, enanthylyl, capryryl, pelargonyl, caproyl, undecyloyl, lauroyl, tridecanoyl, myristoyl, pentadeconoyl, palmitoyl, margaroyl, stearoyl, nondecyloyl, etc. 7

The color formers embraced by the above formula are new entities in that the prior art does not show 5-amin'o Z-naphthols acylated with aroyl groups in thel-position.

In the following list are examples of compounds embraced by the above general formula which have been found to be suitable for producing yellow az'ine dye images:

I HzN HiN .fi-aruino-hbenzoyl- 5-amino-l-(Z-chlorobenzoyl)- NZTnaphthoI .-2,-nap hthol (3) CH: (4) OCH;

OH -OH I HQN nlN 5-amino-1-(4-methyl- 5-amino-1-(4-methoxybonzo 1 benzoyD-Z-naphthol 2-naphthol y r V V 2,921,851

H OBI-C 011 -amino-1-(a-stearamidoben- 5-amino-1-(3-nitrozoyl)-2-naphthol benzoyl)-2-naphtho1 G-amino-l- (4-palmity1- S-amino -1- (3-0 ctadecoxyben- 5-amino-1-(4-stearylaminoben- 5-amino-1-(4-stearzoyl)-2-naphtho1 amidobenzoyl)-2- naphthol The l-aroyl-S-amino-Z-naphthols employed as color formers in this invention can be prepared by the acylation of S-acetamido-Z-naphthol with an aroyl halide in an inert solvent'in the presence of anhydrous aluminum chloride. The resulting S-acetamido-l-aroyl-Z-naphthol is then treated with an acid or base to hydrolyze the acetamido group to the free amine in order to obtain the S-amino-l-aroyl-Z-naphthol.

The color developers which are employed herein are, as previously stated, of the 2,4-diamino aniline type which are described in the aforesaid Schmidt and Tulagin patent. Such developers representative of this class are the following:

11 NH t V (1 NBC H N-GsHsOH NH 7 p NE Hso nooc NE: NH:

The color formers as herein described can either be incorporated in the emulsion or in the developer. If the former is desired, the color former should contain a group to prevent diffusion or wandering from its location in the photographic emulsions. Examples of such non-diffusing color formers are represented by compounds of Formulae 6, 7, 8 and'9. I This invention may be carried out so as to use the color developing method for producing colored negatives, colored positives, or reverse images. These methods are general and conventional in the art and their efiicacy is dependent upon the point at which color development takes place.

It is the opinion of the applicant that the formation of the yellow dye images of the type described herein -may proceed along the lines shown in the following equation, it being understood that such an equation is inserted from a theoretical standpoint and used merely to help explain the invention and that I do not intend to be restricted thereto:

mm huic m I NHGsHaOH HN 01H Magenta acid form: pH less than PREPARATION OF COLOR FORMERS Example I 5-AMINO-1-BENZOYL-2-NAPHTHOLCOMPOUND 1 1-benzoyl-S-acetamido-Z-naphthol (8.0 g.) was placed in a flask with 100 ml. of 3 N sodium hydroxide. The resulting solution was heated under reflux for 1% hours, then diluted with about 200 ml. of water and acidified with acetic acid. The resulting bright yellow solids were collected by filtration and washed with water. The wet cake was dissolved in about 250ml. of hot ethanol, charcoaled and filtered. The filtrate was. warmed and diluted with an equal volume of water, then set aside to. cool and crystallize. After chilling; the crystalline solids were collected on a Biichner funnel, washed once with aqueous methanol and dried. The yield of orangeyellow product was 87% of theory.

Analysis.-Calc.: C-7 7.6; H4.9; N5.3. Found: 0-775; H4.9; N5.4.

Example 11 fi-AMING-I-Q-CHLOROBENZOYD2-NAPHTHOL- COMPOUND 2 1-(2-chlorobenzoyl)-5-acetamido-2-naphthol (0.5 g.) was placed in a 50 ml. round bottom flask with 25 ml. of a mixture consisting of equalvolumes of ethanol and concentrated hydrochloric acid. After refluxing for 2-3 5 hours, the solution was allowed to cool and made alkaline with 6 N sodium hydroxide solution. After charcoaling and filtering, the filtrate was acidified with acetic acid. The orange-red product was collected by filtration, Washed with water and recrystallized by dissolving in a small 10 amount of boiling methanol, diluting to cloud point with water, and setting aside to cool and crystallize. The yield of brick-red product was 0.3 g. with a melting point of 155 C.

Analysis.--Chlorinecalc.: 11.75. Found: 11.8.

, I Example 111 v tS-AMINO-l-P-METHYLBENz0YL-2-NAPHTHOL- COMPOUND 3 f CH:

NHL

1-(4-methylbenzoyl)-5-acetamido-2 naphthol (4.0 g.) was placed in a 50 ml. flask with 30 ml. of a solution consisting of equal volumes of ethanol and hydrochloric acid. After refluxing for 1% hours and cooling, the separated crystals were collected and washed once with cold 6 N hydrochloric acid. The filter cake was then dissolved in about 200 ml. of water with the aid of 6 N sodium hydroxide solution, charcoaled and filtered. The

orange filtrate was acidified with acetic acid and the resulting solids collected and washed with water. The wet filter cake was dissolved in about 100 ml. of hot methanol, charcoaled and filtered. The filtrate was diluted with an equal volume of hot water and set aside to cool and crystallize; The yield of orange colored product was 2.1 g. and had a melting point of 200 C. l Analysis.Nitro2en-calc.: 5.01. Found: 5.04.

Example IV 5-AMINO-1-PMETHOXYBENZOYL-g-NAPHTHOL- COMPOUND 4 OOHa I i OH NH Q5 2 1-(4-methoxybenzoyl)-5-acetamido-2-naphthol (2.5 g.) was placed in a flask containing 20 ml. of a solution consisting of equal volumes of, ethanol and hydrochloric acid. The resulting solution was refluxed for three hours 10 and then made alkaline with 6 N sodium hydroxide solution. After charcoaling a'rd filtering, the filtrate was acidified with acetic acid, the solids collected by filtration and washed with water. The damp filter cake was recrystallized from acetic acid. The yield of crystalline 3; product was 0.3 g. with a. meltingpoint of 235 C.

7 c. l Example if? sat re;-em mmrawn; I; f

N This product was obtainedin an impure state with small yields using the'"sameprocedure as that used'with l NHCOCH;

hydrous aluminum chloride (0.2 mole) was then added portionwise with stirring. When the addition was completed, the reaction was heated on a steam bath for 1 hour. The resulting dark reaction "mixture was poured into about 250 ml. of ice and hydrochloric acid, diluted to about 7 50 mlQand made strongly alkaline with sodium hydroxide solution. After filtering from a slight amount of insoluble material, the layers were separated and the aqueous phase acidified with aceticacid. After collecting the resulting solids on 'a Biichner funnel and washing with water, the damp cake was dissolved in about 250 ml. of hot pyridine containing a small amount of acetic acid, charcoaled and filtered. The hot filtrate was diluted to the cloud point with water and set aside to cool and crystallize. ice and the solids collected by filtration, washed with diluted ethanol, and dried. The yield of pale yellow 7 crystalline produce was 53.3% of theory.

Analysis.-Calc.: C7 4.8; H4.9. Found: 0-746; H-5.0.

Example Vll 5-ACE'1AM1DO- -(2-CHLOROBENZOYL)-2-NAPHTHOI| The mixture was then chilled in Into a 100 ml., 3-necked flask, fitted with a stirrer and thermometer, was placed 25 ml. of dry tetrachloroethane. S-acetamido-Z-naphthol (0.025 mole) was suspended therein followed by 2-chlorobenzoyl chloride (0.025 mole). Anhydrous aluminum chloride powder (0.1 mole) was added portionwise to the chilled suspension (ice bath) with stirring. After stirring an additional hour in the ice bath, the solvent was removed by distillation under vacuum and the yellow glassy residue decomposed by the addition of ice-concentrated hydrochloric acid mixture. The resulting solids were collected by filtration and dissolved in 200 ml. of hot methanol by the addition of'ammonium hydroxide. The resulting solution was treated with charcoal and filtered. The filtratewas diluted with 50 ml. of water and acidified with aceticacid. After chilling, the solids were collected by filtration, washed with water and dried. The yield of light yellow product was 5.4 g. (63.5% of theory) with a melting point of 205-206 C.

' Example VIII.

5-ACETAMIDO -1- (4-METHYLBENZOYL) -2-NAPHTHOL CHz j NBC 0 CH:

- Into a 100 ml., 3-necked flask, fitted with a stirrer and condenser, was placed 25 ml. of tetrachloroethane and 5-acetamido-2-naphthol (0.025 mole) suspended therein followed by 4-methylbenzoyl chloride (0.025 mole). After chilling in an ice bath, anhydrous aluminum chloride powder (0.1 mole) was added portionwise with stirring. When addition was complete, the mixture was then stirred in the ice bath for 1 hour at room temperature for an additional hour and finally heated to reflux for 10-15 minutes. After cooling, the mixture was poured into about 250ml: of ligroin and the solids'collected by filtrationp The gummy filter cake was dis solved in 200ml. of water with the aid of 6 N sodium hydroxide and-filtered'from any insoluble material. The filtrate was treated with'charcoal and refiltered. i After acidification of the filtrate to' pH 5 with o N hydrochloric acid, the resulting solids were collected by filtration and washed with water. The yield of pale yellow product was 4.6 g. which hada melting point of 2 l9220-C. 5

.It-wassubse'quently determined that the coupler intermediates-ofthetype described herein are preferably obtaind. by .an application of the Fries rearrangement'on the benzoic acid esters ofthe above 6 -acetamido-2- The preparation of the following coupler intermediate illustrates this mode of synthesis:

Exainple IX 5-ACETAMIDO-I-P-IIETHVOXYBENZOYL-2NAPHTHOL 'OCH:

NHCOOH:

Flnto a round bottom had: was placed .20 ml. :of tetrachloroethane followed by S-acetamido-Z-naphthol, 1pmethoxybenzoate (01013 'mole) and anhydrous aluminum chloride powder (0.013 mole). The reactants were heated to reflux for 10-15 minutes and allowed to cool. The residue was treated with ligroin, filtered and washed with ether. The filter cakewas then suspended in 150 ml. of water and dissolved 'by the addition of 6 N sodium hydroxide solution, =charcoaled and filtered. The yellow filtrate was acidified with .6 N hydrochloric acid and the yellow solids collectedby filtration and washed with water. The yield of product was 2.5 g. which had a melting point of about 280 C.

The 5-acetamido-2-naphthol, p-methoxybenzoate used in the above reaction was prepared as follows:

Into a 50-ml., B-necked flask was placed '25 ml. of tetrachloroethane,.5vacetamido-2-naphthol (0.025 mole), and p-methoxyben'zoyl'chlofide (0.025 mole). This mixture was-chilled -in-an ice bath' and anhydrous aluminum chloride powder (:1 mole) was added portionwise with stirring. After stirring cold for lhour, the ice bath was removed-and stirring'continued "for an additional two hours. The solvent was then decanted from the gum which was then decomposed with an ice-hydrochloric acid mixture. An oil separated which was solidifled by shaking with ether, the solids were filtered and washed with ether. Upon recrystallization from methanol, 4.5 g. of white solid was obtained with a melting point of 150 C.

An alternative, and possibly a better method of obtaining the esters in most cases would be to utilize the standard procedure of the Schotten-Baumann reaction which consists of reacting the aroyl chloride with the naphthol ina sodium hydroxide solution.

The following example illustrates the manner whereby the couplers herein described are incorporated in a gelatin emulsion:

Example X To 100 ml. of a developer solution made up as follows:

was added a solution of 0.2 g. of S-amino-l-benzoyl-Z- naphthol (Formula 1) dissolved in ml. of 2 N sodium hydroxide solution. A strip of positive film carrying a silver halide image was treated in this developer-color former solution for ten minutes at C. with agitation. The strip was then washed for five minutes in running water at 18 C., and then bleached in a ferricyanidebromide bleach until all the developed silver was converted into silver bromide. The strip was then washed until free from bleach and then fixed in acid-hypo. At this point, the strip carried a reddish-magenta dye image which was an exact duplicate of the original silver halide image. After the strip had been washed free of hypo, it was treated in a 5% solution of sodium carbonate until the reddish-magenta image was completely converted to a brilliant yellow dye image, about 1 minute being sufficient for the conversion. The so obtained yellow image was stable to washing and dried, showed excellent light fastness and displayed no tendency to undergo a spectral shift when subjected to conditions as low as pH 5.

Alternately, the coupler may be incorporated in the photographic silver halide emulsion in which case one of the non-diffusing type is advantageously employed such as those represented by Formula 7 or 9.

10 *Iellaim':-

4 1. A photographic silver halide emulsion containing as acolor .former fcapable' of yielding a yellow :azine dyestufi image when color developed with a 2,4-rdiaminoanil'me developer, a compound :of :the following fonmila:

3. A photographic silver halide emulsion containing as a color former a compound of the following formula:

NHC O CnHas 4. The process of producing yellow azine dyestuff images by color-forming development which comprises exposing a silver halide emulsion and developing the same with a 2,4-diamino-aniline in the presence of a color former having the following formula:

'11 1 2' wherein R is selected from the class consistinglof hy- 6. The -proccss as defined inclaim 4owhcrcin thc color dro'gfi, nitro,alkoxy,.alkyl and .-NHR' whcrcinoR' is former has the following formula: :7 selected from the class consisting of alkyl 'and aliphatic l i, I NEcocnHiu, acyl groups. I 5; The process as defined in claim 4 whcreinrthe color 5 former has the following formula: 1

V ab 7 10 l I 03 15 V a: j v 1 Refcrences (Zitc'dthe file of this p 1cm I UNITED'STA'I ESQI ATENTS v V no. 7 c 2, s25,s o3 .Tulaginct-a1.,.;.. ..c----.v [10,1950 ,E E W' A 332,479 r .L, .-,Nov. 24, 1941' 

1. A PHOTOGRAPHIC SILVER HALIDE EMULSION CONTAINING AS A COLOR FORMER CAPABLE OF YIELDING A YELLOW AZINE DYESTUFF IMAGE WHEN COLOR DEVELOPED WITH A 2,4-DIAMINOANILINE DEVELOPER, A COMPOUND OF THE FOLLOWING FORMULA: 